diff --git a/sbt/src/main/scala/sbt/ScalaProject.scala b/sbt/src/main/scala/sbt/ScalaProject.scala
index bbabf3b96..ef39107a4 100644
--- a/sbt/src/main/scala/sbt/ScalaProject.scala
+++ b/sbt/src/main/scala/sbt/ScalaProject.scala
@@ -192,7 +192,7 @@ trait ScalaProject extends SimpleScalaProject with FileTasks with MultiTaskProje
 	def scaladocTask(label: String, sources: PathFinder, outputDirectory: Path, classpath: PathFinder, options: ScaladocOption*): Task =
 		scaladocTask(label, sources, outputDirectory, classpath, options)
 	def scaladocTask(label: String, sources: PathFinder, outputDirectory: Path, classpath: PathFinder, options: => Seq[ScaladocOption]): Task =
-		task
+		fileTask(outputDirectory / "index.html" from sources)
 		{
 			val optionsLocal = options
 			val maxErrors = maximumErrors(optionsLocal)